Basic Fins Command Format - Omron CS CJ1W-ETN21 Operation Manual

Using Socket Services with CMND(490)
6-8-3

Basic FINS Command Format

0
Command
code
138
Program Flow
Check socket status.
Is Bit 15 (Open Flag) in the socket status word for
the socket being used OFF?
(Checks to see if the socket is open before com-
munications and close processing.)
Check the Port Enabled Flag.
Is the Port Enabled Flag in A502 for communica-
tions port ON?
Execute FINS command (via CMND(490)) for Ethernet Unit.
Use the CMND(490) to send the UDP OPEN RE-
QUEST command (2701) to the Ethernet Unit.
Check response.
Is the response code = 0000 (normal) for the
UDP OPEN REQUEST command?
Check Opening Flag status.
Wait until bit 00 in the socket status turns OFF
(open complete).
Check results storage area response code.
Is response code = 0000?
The basic format for FINS commands used for socket services is shown in the
following diagram.
1 2 3 4 5 6 7
Results storage area
Socket number
Socket option
Command Code:
Specifies the process code requested from the socket.
Socket Option
For the TCP OPEN REQUEST (ACTIVE or PASSIVE) command, specifies
whether or not the keep-alive function is to be used.
Socket Number
Specifies the socket number for the process, between 1 and 8.
Results Storage Area
Specifies the area to store the results of the requested process.
Parameters
Specifies the parameters defined for the command code.
Start UDP Open
OFF?
YES
ON?
YES
0000?
YES
ON/OFF
0000?
YES
UDP opened
Byte order from the
8 9 10 11 12
beginning of the frame
Parameters
Section 6-8
Error Evaluation
The specified UDP socket is
NO
already open.
The specified port is running
NO
network communications.
An error occurred. The Ethernet
Unit did not receive the UDP
NO
OPEN REQUEST command.
(Socket status bit 00)
An error occurred. The specified
socket could not be opened.
NO